Fsilva: /* Step 2: verification with the selected source, using the large domain */

2020-07-02T08:47:14Z

Step 2: verification with the selected source, using the large domain

Goulet at 22:52, 24 June 2020

2020-06-24T22:52:23Z

Goulet: /* Step 1: selection and verification of source model using the small domain */

2020-06-24T22:51:10Z

Step 1: selection and verification of source model using the small domain

Goulet: Created page with "This page documents the High-F activities and decisions for the 2020 verification runs for four groups: Olsen et al. (AWP), Graves (RWG) and Taborda, Restrepo et al. (Hercules..."

2020-06-24T22:50:08Z

Created page with "This page documents the High-F activities and decisions for the 2020 verification runs for four groups: Olsen et al. (AWP), Graves (RWG) and Taborda, Restrepo et al. (Hercules..."

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This page documents the High-F activities and decisions for the 2020 verification runs for four groups: Olsen et al. (AWP), Graves (RWG) and Taborda, Restrepo et al. (Hercules), Breuer (Edge). Verification of 5 Hz time series (4Hz PSA, multiple bands verification) using La Habra stations.

== USGS Earthquake Information ==
*[[La Habra Earthquake]]

== Observational Data ==
*[[La_Habra_Observational_Data]]
*[[Selection_of_La_Habra_Ground_Motion_Observations]]

== Region Definitions ==
*[[La_Habra_Simulation_Region]]
*[[La Habra Simulations on Titan]]

== Mesh generation rules and parameter constraints ==
=== Velocities ===
* 1. Set Min Vs=500 m/s
* 2. If Vs was lower than 500 m/s and adjusted, then adjust Vp with original Vp/Vs ratio (so that we don’t have the automatic Vs/Vp of 3). We may want to set a minimum value of Vp (Rob to check)
* 3. Then set Max Vp/Vs= 3, if lower Vp to maintain the max of 3 ratio

=== Lame parameters (mu and lambda) ===
Use mu and Lambda parameters to fix Vp/Vs issues in the CVM where necessary, as part of the mesh generation. Need to make sure that patches are physical and not only to make the codes run.
* Rob to check if raw model produces lambda of <=zero.
* Note: lambda of zero corresponds to Vp/Vs= sqrt(2)=1.45
* Note: typical Vp speeds are 330 m/s in air, 1450 m/s in water and about 5000 m/s in granite

=== Anelastic attenuation (Q) ===
Frequency-independent Q definition
* Qs=100*Vs(km/s)
* Qp=2*Qs

=== Upper frequency ===

* 5Hz: based on 500 m/s and 20 m spacing
* Kim and Rob have been low-pass filtering the slip function at 5 Hz
* Ricardo and Naeem don’t filter the source

== Source Models ==
We discussed various sources, both point source (PS) and finite-fault (FF) in the past for our verifications and validation.
* Various models were run in 2016:
** [https://scec.usc.edu/scecpedia/HighF_v14.12_Data_Comparison#Simulation_Results_-_22_May_2016 2016 runs with 2FF and 1 PS]

* Also ran various smoothed variations of the GP15 FF (need to find a reference for that)

* Rob to follow-up with Wei (last communication was in April 2017).

Proposed models for verification and validation:
*PS: model from En-Jui (moment tensor). Can we replicate En-Jui's results? Would need to use CVMS4.26 (cms5) - not desirable. We could perform a check with CVS4.26.M01 at 5 sec. Need to use the same record En-Jui used. Proposed to use records from Figure 6 in:
** Lee E.-J., P. Chen, and T.H. Jordan (2014). Testing Waveform Predictions of 3D Velocity Models against Two Recent Los Angeles Earthquakes. Seismol. Res. Lett., 85 (6): 1275–1284 ([http://hypocenter.usc.edu/var/www/html/research/High-F_2018/Lee%2C%20Chen%2C%20Jordan%20-%202014%20-%20Testing%20Waveform%20Predictions%20of%203D%20Velocity%20Models%20against%20Two%20Recent%20Los%20Angeles%20Earthquakes.pdf Paper here])
*FF: [http://hypocenter.usc.edu/research/High-F_2018/LaHabra_notes-20170412-presented-2017-04-24.pdf Summary of agreed-upon FF model (gp.5.3.02)]
* FF refined with velocity model [http://hypocenter.usc.edu/research/High-F_2018/rwg_slides-20180221.pptx Slides from Graves presented on Feb. 21 2018]

== Path forward on VERIFICATION paper ==
=== Misc definitions ===
==== Domains ====
*Small domain: defined [https://scec.usc.edu/scecpedia/La_Habra_Simulation_Region here].
*Large domain: defined [https://scec.usc.edu/scecpedia/HighF_v14.12#Simulation_Box_.2F_Velocity_Model here].
*Proposed medium domain:
<pre>
The four corners of medium La Habra Simulation domain are:
c1= -118.387131 33.887287
c2= -117.970993 34.301479
c3= -117.472496 33.955025
c4= -117.889359 33.542511
And the model dimensions are:
xlen= 60.0000 km
ylen= 60.0000 km
zlen= 25.0000 km

Note that this is not a UTM projection. It is transverse Mercator with spherical reference and corresponds very closely to the proj4 projection:
+proj=tmerc +lat_0=%f +lon_0=%f +ellps=sphere +a=6378139.0 +b=6378139.0 +units=m +no_defs

where lat_0, lon_0 are the domain center coordinates, which in this case are: lon= -117.930000 lat= 33.922000
</pre>

The regional seismic velocity model used by all modelers is: CVMS4.26.M01 (called cvmsi in UCVM, as per Table 1 in this [http://hypocenter.usc.edu/research/High-F_2020/Small_et_al_2017_SCEC_UCVM.pdf UCVM paper]), do NOT apply a GTL to the model, but [https://scec.usc.edu/scecpedia/HighF_2018#Mesh_generation_rules_and_parameter_constraints apply the rules described here].

==== Vs30 at recording stations ====
* For interpretation of recorded data, use in order of preference
** values listed as "Vs30 (m/s) selected for analysis" in the NGA-West2 database flatfile
** if stations are not included in the NGA-West2 database, we will use the values from Will et al. 2015 as retrieved from UCVM (with interpolation)
* For interpretation of simulation data
** We retrieved the Vs30 values using UCVM v19.4 for CVM-S4.26.M01 (cvmsi), for CVM-S4.26 (to show impact of adding .M01 GTL), for CVM-S4 (to check if Vs30 matches .M01 exactly), and from the Wills 2015 Vs30 model embedded in UCVM.
* For the Vs30_query against the models uses a slowness algorithm, and a 1 meter spacing.
* The Wills 2015 Vs30 values are based a processing sequence that includes converting a GIS shape file into a rasterized Vs30 grid of values produced by Kevin Milner. Kevin provided a file raster_0.00025.flt, which is rasterized with 0.00025 degree spacing (~25 meters). This file is then used to generate an etree which is used to stored the rasterized data. When query points are given between grid points, then ucvm implements interplolation of Vs30 values between associated grid points. More
* More details on the Willis Map integration here: [[Wills Map]].
* Descriptions of UCVM Vs30 Slowness algorithm here: [[UCVM_Vs30]].
* Description of CyberShake Vs30 Slowness algorithm here: [[CyberShake_Code_Base#Stochastic%20codes]]

=== Step 1: selection and verification of source model using the small domain ===
* Use medium domain, with Vs floor of 500 m/s (CVMS4.26-M01 (cmvsi)) and constraints, [https://scec.usc.edu/scecpedia/HighF_2018#Mesh_generation_rules_and_parameter_constraints as described here]
* We agreed that all the modelers will use a version of the medium domain that is rotated by 39.9 degrees, so as to remove a source of difference we can control. We observed different results due to rotation of the domain in CyberShake simulations a few months ago, for which we could not account for by considering the model edges and boundary effects. There seems to be some anisotropy in the model that may be due to the staggered grid.
==== BBP Station List ====
* Focused on 15 near-by stations selected by Rob

{| class="wikitable"
|+UCVM Vs30 Values
|-
|Station Id
|Lat - NGA-West2
|Lon - NGA-West2
|Vs30 - NGA-West2
|Vs30 - Wills 2015 (UCVM v19.4)
|Vs30 - Slowness Method (1m res) CVM-S4.26.M01 (cvmsi) (UCVM v19.4)
|-
| CE_13066
| -117.9568
| 33.8401
| 288.00
| 293.500
| 284.461
|-
| CE_13849
| -117.8180
| 33.8535
| 385.00
| 351.900
| 329.762
|-
| CE_13878
| -117.8870
| 33.8891
| 398.00
| 313.585
| 344.043
|-
| CE_13879
| -117.9591
| 33.8663
| 299.00
| 228.200
| 287.845
|-
| CE_13880
| -117.9311
| 33.9086
| 324.00
| 386.600
| 349.812
|-
| CE_13881
| -117.9557
| 33.9315
| 353.00
| 386.600
| 349.317
|-
| CE_13882
| -117.8034
| 33.9274
| 412.00
| 385.100
| 367.423
|-
| CE_13883
| -117.8578
| 33.8534
| 300.00
| 228.200
| 329.762
|-
| CE_14026
| -118.0469
| 33.8892
| 281.00
| 228.200
| 287.845
|-
| CE_14027
| -118.0576
| 33.9283
| 342.00
| 386.600
| 354.637
|-
| CE_23938
| -117.8657
| 34.0209
| 402.00
| 418.980
| 370.670
|-
| CI_BRE
| -117.9812
| 33.8078
| 238.00
| 228.200
| 285.871
|-
| CI_FUL
| -117.9225
| 33.8717
| 309.00
| 293.500
| 362.574
|-
| CI_OLI
| -117.9237
| 33.9454
| 328.00
| 385.433
| 331.459
|-
| CI_WLT
| -117.9508
| 34.0095
| 265.00
| 293.500
| 309.646
|}

The BBP station list was updated to include station latitude and longitude coordinates up to 4 decimal places. It includes the Vs30 from the NGA-West2 flat file, updated on May 12th, 2020.

-117.9568 33.8401 CE_13066 288.00 0.1250 4.0000
-117.8180 33.8535 CE_13849 385.00 0.1250 4.0000
-117.8870 33.8891 CE_13878 398.00 0.1250 4.0000
-117.9591 33.8663 CE_13879 299.00 0.1250 4.0000
-117.9311 33.9086 CE_13880 324.00 0.1250 4.0000
-117.9557 33.9315 CE_13881 353.00 0.1250 4.0000
-117.8034 33.9274 CE_13882 412.00 0.1250 4.0000
-117.8578 33.8534 CE_13883 300.00 0.1250 4.0000
-118.0469 33.8892 CE_14026 281.00 0.1250 4.0000
-118.0576 33.9283 CE_14027 342.00 0.1250 4.0000
-117.8657 34.0209 CE_23938 402.00 0.1250 4.0000
-117.9812 33.8078 CI_BRE 238.00 0.1250 4.0000
-117.9225 33.8717 CI_FUL 309.00 0.1250 4.0000
-117.9237 33.9454 CI_OLI 328.00 0.1250 4.0000
-117.9508 34.0095 CI_WLT 265.00 0.1250 4.0000

==== Source model ====
* Use RWG best source:
** Rob ran a series of tests to select a finite source to use with the Vmod floored at 500 m/s ([http://hypocenter.usc.edu/research/High-F_2020/source_nearfault-20200217.pptx powerpoint here])
** The suite of 40 SRF rupture models for the 2.5 km X 2.5 km fault are contained in this [http://hypocenter.usc.edu/research/High-F_2020/m5.14-2.5x2.5.tgz tarfile (364 MB)]. There are 2 resolutions: 100 m subfaults and 20m subfaults. The recommendation is to use 20m subfaults if possible.
* Verify that best RWG source is good at 15 stations for all models. This is a first-order test for the purpose of the verification paper only, modelers can chose another source for the validation paper later, if, for example, they use another velocity model or different constraints.
*Step 1 was completed on June 17 during our call, at which time we moved to Step 2 below. [http://hypocenter.usc.edu/bbp/highf/2020-06-18/combined-06-17/ Combined results from all groups here!]

=== Step 2: verification with the selected source, using the large domain ===
* Then all modelers rerun large region
** We agreed to keep the same rotation as for the small domain (39.9 degrees)
** need to review the station list and post it HERE
* Perform verification using results and plots from
** tsprocess time series/FAS/PSA combo plots
** tsprocess Anderson GOF scores and maps (GMT capability needs to be restored due to updates)
** BBP (GOF with T, distance, mapped, etc.; consider adding Vs30-based plots on BBP)
* Compare with 1D BBP sims (with Vs30=500 for all stations, with site response)?

=== Step 3: write paper, publish ===

== Related Pages ==
*[https://scec.usc.edu/scecpedia/High-F_Project High-F Main page]

*[https://scec.usc.edu/scecpedia/HighF_v14.12 High-F 14.12 description of parameters for verification and validation]

*[https://scec.usc.edu/scecpedia/HighF_v14.12_Data_Comparison Past verification (HighF_v14.12_Data)]

*[https://scec.usc.edu/scecpedia/La_Habra_Simulation_Region La Habra Simulation region (small domain)]

*[https://scec.usc.edu/scecpedia/La_Habra_Simulations_on_Titan La Habra simulations on Titan]

*[https://scec.usc.edu/scecpedia/La_Habra_Observational_Data La Habra Observational data]

@@ Line 238: / Line 238: @@
 * Then all modelers rerun large region
 ** We agreed to keep the same rotation as for the small domain (39.9 degrees)
-** need to review the station list and post it HERE
+** Revised station list available ([http://hypocenter.usc.edu/research/High-F/la_habra_v20_07_1.stl here])
 * Perform verification using results and plots from
 ** tsprocess time series/FAS/PSA combo plots

@@ Line 87: / Line 87: @@
 * Descriptions of UCVM Vs30 Slowness algorithm here: [[UCVM_Vs30]].
 * Description of CyberShake Vs30 Slowness algorithm here: [[CyberShake_Code_Base#Stochastic%20codes]]
 === Step 1: selection and verification of source model using the small domain ===
@@ Line 249: / Line 248: @@
 == Related Pages ==
 *[https://scec.usc.edu/scecpedia/High-F_Project High-F Main page]

@@ Line 92: / Line 92: @@
 * Use medium domain, with Vs floor of 500 m/s (CVMS4.26-M01 (cmvsi)) and constraints, [https://scec.usc.edu/scecpedia/HighF_2018#Mesh_generation_rules_and_parameter_constraints as described here]
 * We agreed that all the modelers will use a version of the medium domain that is rotated by 39.9 degrees, so as to remove a source of difference we can control. We observed different results due to rotation of the domain in CyberShake simulations a few months ago, for which we could not account for by considering the model edges and boundary effects. There seems to be some anisotropy in the model that may be due to the staggered grid.
-==== BBP Station List ====
+===== BBP Station List =====
 * Focused on 15 near-by stations selected by Rob
@@ Line 229: / Line 229: @@
   -117.9508 34.0095  CI_WLT  265.00  0.1250  4.0000
-==== Source model ====
+===== Source model =====
 * Use RWG best source:
 ** Rob ran a series of tests to select a finite source to use with the Vmod floored at 500 m/s ([http://hypocenter.usc.edu/research/High-F_2020/source_nearfault-20200217.pptx powerpoint here])

HighF La Habra Verification - Revision history

Fsilva: /* Step 2: verification with the selected source, using the large domain */

Goulet at 22:52, 24 June 2020

Goulet: /* Step 1: selection and verification of source model using the small domain */

Goulet: Created page with "This page documents the High-F activities and decisions for the 2020 verification runs for four groups: Olsen et al. (AWP), Graves (RWG) and Taborda, Restrepo et al. (Hercules..."